The jobs of workers on an offshore oil rig are at risk as a Norfolk energy company has yet to confirm whether it will renew its contract with their employer.

Management at Rowan Drilling UK have told an undisclosed number of staff their positions are “at risk” when its contract with Norwich-based offshore firm Perenco comes to an end.

The contract’s renewal – and the future of the workers’ jobs – hinge on the success of drilling tests by Perenco.

And a Norfolk-based employee of Rowan Drilling, which has its head office in Aberdeen, said East Anglian jobs could be at risk as well as Scottish ones.

A letter, seen by this newspaper, to staff on the Rowan Gorilla VII jack-up rig in the North Sea said there will be a 30-day consultation period during which the company will “investigate all alternative options” – which could include finding staff work on other rigs in its fleet.

The employee, who wished to remain anonymous, said morale among staff on board was at “rock bottom”.

“We have been suspicious something was going on but the management do keep us in the dark. The rig is full of workers from East Anglia as well as from all over the UK.”

The letter to staff on Rowan Gorilla VII, signed by general manager Eric Wesselingh, said: “We appreciate this news is disconcerting.

“Our industry continues to face uncertainty; continued reduced activity and highly competitive market conditions have led to shorter term contracts and contractual options not being extended.”

Documents from The Rowan Companies, Rowan Drilling’s American parent group, say the contract with Perenco had an estimated duration of up to 200 days and is due to end later this year, with 91 days set aside in the fourth quarter of 2017 and first quarter of 2018 for repairs and inspections.

A spokesman for The Rowan Companies said: “Rowan confirms it has started the process of consultation with its employees assigned to the Rowan Gorilla VII since the primary term of its current contract with Perenco is coming to an end in the near future and there is currently no firm contract in place for work on that rig moving forward.”

Perenco, which has its head office at St Andrews Business Park, declined to comment.

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